CVE-2025-48038 is a resource allocation vulnerability identified in the Erlang Open Telecom Platform (OTP), specifically affecting the ssh and ssh_sftp modules within the lib/ssh/src/ssh_sftpd.erl file. The vulnerability is classified under CWE-770 (Allocation of Resources Without Limits or Throttling) and CWE-400 (Uncontrolled Resource Consumption). It affects OTP versions from 17.0 up to 28.0.3, including specific patch versions 27.3.4.3 and 26.2.5.15, and ssh package versions from 3.0.1 through 5.3.3, 5.2.11.3, and 5.1.4.12. The flaw allows an attacker to cause excessive allocation of resources, potentially leading to resource exhaustion or leaks. This can degrade system performance or cause denial of service (DoS) conditions by overwhelming the ssh_sftp server component with requests that are not properly throttled or limited. The vulnerability does not require user interaction, privileges beyond low-level privileges, or authentication, and can be exploited remotely over the network. The CVSS v4.0 score is 5.3 (medium severity), reflecting the network attack vector, low attack complexity, no privileges or user interaction required, and limited impact on availability. No known exploits are currently reported in the wild, and no patches have been linked yet, indicating that mitigation may rely on vendor updates or configuration changes once available.

For European organizations, this vulnerability poses a moderate risk primarily to systems running Erlang OTP with the affected ssh/ssh_sftp modules, which are commonly used in telecommunications, messaging platforms, and distributed systems. An attacker could exploit this vulnerability to cause denial of service by exhausting server resources, impacting availability of critical services such as secure file transfers and remote management. This could disrupt business operations, especially in sectors relying on Erlang-based infrastructure like telecom providers, financial services, and cloud service providers. The lack of authentication requirement increases the risk of exploitation from external attackers. While the impact on confidentiality and integrity is low, the availability impact could be significant for organizations with high uptime requirements. European organizations with large-scale Erlang deployments or those providing services dependent on OTP-based ssh servers are particularly at risk of operational disruption and potential reputational damage.

Until official patches are released, European organizations should implement specific mitigations such as: 1) Monitoring and limiting the rate of incoming ssh_sftp connections and requests using network-level rate limiting or firewall rules to prevent resource exhaustion. 2) Deploying resource quotas and limits at the operating system level (e.g., cgroups on Linux) to restrict CPU, memory, and file descriptor usage by OTP ssh processes. 3) Isolating Erlang OTP ssh services in dedicated containers or virtual machines to contain potential resource abuse. 4) Enabling detailed logging and alerting for unusual ssh_sftp activity patterns to detect potential exploitation attempts early. 5) Reviewing and restricting network exposure of ssh_sftp services to trusted networks only, minimizing attack surface. 6) Planning and prioritizing patch deployment once vendor updates become available, including testing in staging environments. These targeted mitigations go beyond generic advice by focusing on resource control and network-level protections specific to the vulnerable components.